Generally, domestic sewing machines and industrial sewing machines are provided with a handwheel on the right-hand side of the frame. The handwheel is connected to the main shaft for rotation together with the main shaft. Prior to starting the sewing operation, the handwheel is rotated slightly in the forward or reverse direction by the operator so as to vertically move a needle bar which is interlocked through means of a crank mechanism with the main shaft. For example, the needle bar is lowered by rotating the handwheel so as to facilitate positioning fabric work for aligning a sewing starting position on the fabric with the needle location, or alternatively the needle bar is raised by rotating the handwheel so as to facilitate replacement of the presser foot and the needle.
As mentioned above, the handwheel is necessary for the manual operation of the sewing instrumentalities only in preparing for performance of the sewing operation and once the sewing operation is started, the handwheel is never used. Even though the handwheel is infrequently used, it always occupies a position projecting outwardly from the right-hand side of the frame. This tends to make the sewing machine obsolete in appearance and affords little scope for a novel design to be introduced into the sewing machine. Moreover, when carrying the sewing machine, the handwheel projecting outwardly from the frame may often strike against a solid object thereby causing damage to the handwheel. Thus, in general, the handwheel is merely a nuisance when the sewing machine is not being operated.
Furthermore, since the handwheel always projects outwardly from the frame during the sewing operation, the rotary motion of the handwheel is dangerous to the operator. Still further, the disposition of the handwheel outside of the frame requires a machine cover to have additional capacity for accommodating the handwheel and therefore, the machine necessitates a large space for installation.